<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">

    <title>猜数字游戏</title>

    <style>
      html {
        font-family: sans-serif;
      }

      body {
        width: 50%;
        max-width: 800px;
        min-width: 480px;
        margin: 0 auto;
      }

      .lastResult {
        color: white;
        padding: 3px;
      }
    </style>
  </head>

  <body>
    <h1>猜数字游戏</h1>

    <p>我刚才随机选定了一个100以内的自然数。看你能否在 10 次以内猜中它。每次我都会告诉你所猜的结果是高了还是低了。</p>

    <div class="form">
      <label for="guessField">请猜数: </label>
      <input type="text" id="guessField" class="guessField">
      <input type="submit" value="确定" class="guessSubmit">
    </div>

    <div class="resultParas">
      <p class="guesses"></p>
      <p class="lastResult"></p>
      <p class="lowOrHi"></p>
    </div>

    <script>
        let randomNumber = Math.floor(Math.random()*100) + 1;
        const guesses = document.querySelector('.guesses');
        const lastResult = document.querySelector('.lastResult');
        const lowOrHi = document.querySelector('.lowOrHi');

        const guessSubmit = document.querySelector('.guessSubmit');
        const guessField = document.querySelector('.guessField');
        
        let guessCount = 1;
        let resultButton;
        guessField.focus()


        function checkGuess() {
            let userGuess = Number(guessField.value);
            if (guessCount === 1){
                guesses.textContent = '上次猜的数：';
            }

            guesses.textContent += userGuess + ' ';

            if (userGuess === randomNumber){
                lastResult.textContent = '恭喜你！猜对了';
                lastResult.style.backgroundColor = 'green';
                lowOrHi.textContent = ''
                setGameOver();
            }else if (guessCount === 10){
                lastResult.textContent = '!!!GAME OVER!!!';
                setGameOver();
            }else{
                lastResult.textContent = '你猜错了！';
                lastResult.style.backgroundColor = 'red';
                if (userGuess < randomNumber){
                    lowOrHi.textContent = '你猜低了！';

                }else if(userGuess > randomNumber){
                    lowOrHi.textContent = '你猜高了'
                }
            }
            guessCount++;
            guessField.value = '';
            guessField.focus();

        };
        guessSubmit.addEventListener('click', checkGuess);
        function setGameOver() {
            guessField.disabled = true;
            guessSubmit.disabled = true;
            resetButton = document.createElement('button');
            resetButton.textContent = '开始新游戏';
            document.body.appendChild(resetButton);
            resetButton.addEventListener('click',resetGame)
        }
        function resetGame() {
            guessCount = 1;
            const resetParas = document.querySelectorAll('.resultParas p')
            for (let i = 0 ; i < resetParas.length;i++){
              resetParas[i].textContent = '';
            }
            resetButton.parentNode.removeChild(resetButton);

            guessField.disabled = false;
            guessSubmit.disabled = false;
            guessField.value = '';
            guessField.focus();


            lastResult.style.backgroundColor = 'white';
            randomNumber = Math.floor(Math.random() * 100) +1
        }
    </script>
  </body>
</html>